Copy linux-imx@xxxxxxx and more related guys to comment
On Wed, Jun 13, 2018 at 8:21 PM, Dong Aisheng <dongas86@xxxxxxxxx> wrote:
> Hi Oleksij,
>
> On Fri, Jun 1, 2018 at 2:58 PM, Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> wrote:
>> The Mailbox controller is able to send messages (up to 4 32 bit words)
>> between the endpoints.
>
> Could we really be able to send up to 4 42bit words with this driver?
>
> It looks to me the current Mailbox framework is more designed for share mem
> transfer which does not fit i.MX MU well.
>
>>
>> This driver was tested using the mailbox-test driver sending messages
>> between the Cortex-A7 and the Cortex-M4.
>
> Would you please provide a guide on how to test it quickly?
> I may want to give a test.
>
>>
>> Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
>> ---
>> drivers/mailbox/Kconfig | 6 +
>> drivers/mailbox/Makefile | 2 +
>> drivers/mailbox/imx-mailbox.c | 289 ++++++++++++++++++++++++++++++++++
>> 3 files changed, 297 insertions(+)
>> create mode 100644 drivers/mailbox/imx-mailbox.c
>>
>> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
>> index a2bb27446dce..e1d2738a2e4c 100644
>> --- a/drivers/mailbox/Kconfig
>> +++ b/drivers/mailbox/Kconfig
>> @@ -15,6 +15,12 @@ config ARM_MHU
>> The controller has 3 mailbox channels, the last of which can be
>> used in Secure mode only.
>>
>> +config IMX_MBOX
>> + tristate "iMX Mailbox"
>> + depends on SOC_IMX7D || COMPILE_TEST
>> + help
>> + Mailbox implementation for iMX7D Messaging Unit (MU).
>> +
>> config PLATFORM_MHU
>> tristate "Platform MHU Mailbox"
>> depends on OF
>> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
>> index cc23c3a43fcd..ba2fe1b6dd62 100644
>> --- a/drivers/mailbox/Makefile
>> +++ b/drivers/mailbox/Makefile
>> @@ -7,6 +7,8 @@ obj-$(CONFIG_MAILBOX_TEST) += mailbox-test.o
>>
>> obj-$(CONFIG_ARM_MHU) += arm_mhu.o
>>
>> +obj-$(CONFIG_IMX_MBOX) += imx-mailbox.o
>> +
>> obj-$(CONFIG_PLATFORM_MHU) += platform_mhu.o
>>
>> obj-$(CONFIG_PL320_MBOX) += pl320-ipc.o
>> diff --git a/drivers/mailbox/imx-mailbox.c b/drivers/mailbox/imx-mailbox.c
>> new file mode 100644
>> index 000000000000..2bc9f11393b1
>> --- /dev/null
>> +++ b/drivers/mailbox/imx-mailbox.c
>> @@ -0,0 +1,289 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/kernel.h>
>> +#include <linux/mailbox_controller.h>
>> +#include <linux/module.h>
>> +#include <linux/of_device.h>
>> +
>> +/* Transmit Register */
>> +#define IMX_MU_xTRn(x) (0x00 + 4 * (x))
>> +/* Receive Register */
>> +#define IMX_MU_xRRn(x) (0x10 + 4 * (x))
>> +/* Status Register */
>> +#define IMX_MU_xSR 0x20
>> +#define IMX_MU_xSR_TEn(x) BIT(20 + (x))
>> +#define IMX_MU_xSR_RFn(x) BIT(24 + (x))
>> +#define IMX_MU_xSR_BRDIP BIT(9)
>> +
>> +/* Control Register */
>> +#define IMX_MU_xCR 0x24
>> +/* Transmit Interrupt Enable */
>> +#define IMX_MU_xCR_TIEn(x) BIT(20 + (x))
>> +/* Receive Interrupt Enable */
>> +#define IMX_MU_xCR_RIEn(x) BIT(24 + (x))
>> +
>> +#define IMX_MU_MAX_CHANS 4u
>> +
>> +struct imx_mu_priv;
>> +
>> +struct imx_mu_cfg {
>> + unsigned int chans;
>> + void (*init_hw)(struct imx_mu_priv *priv);
>> +};
>> +
>> +struct imx_mu_con_priv {
>> + int irq;
>> + unsigned int bidx;
>> + unsigned int idx;
>> +};
>> +
>> +struct imx_mu_priv {
>> + struct device *dev;
>> + const struct imx_mu_cfg *dcfg;
>> + void __iomem *base;
>> +
>> + struct mbox_controller mbox;
>> + struct mbox_chan mbox_chans[IMX_MU_MAX_CHANS];
>> +
>> + struct imx_mu_con_priv con_priv[IMX_MU_MAX_CHANS];
>> + struct clk *clk;
>> +};
>> +
>> +static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
>> +{
>> + return container_of(mbox, struct imx_mu_priv, mbox);
>> +}
>> +
>> +static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs)
>> +{
>> + iowrite32(val, priv->base + offs);
>> +}
>> +
>> +static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs)
>> +{
>> + return ioread32(priv->base + offs);
>> +}
>> +
>> +static u32 imx_mu_rmw(struct imx_mu_priv *priv, u32 offs, u32 set, u32 clr)
>> +{
>> + u32 val;
>> +
>> + val = imx_mu_read(priv, offs);
>> + val &= ~clr;
>> + val |= set;
>> + imx_mu_write(priv, val, offs);
>> +
>> + return val;
>> +}
>> +
>> +static irqreturn_t imx_mu_isr(int irq, void *p)
>> +{
>> + struct mbox_chan *chan = p;
>> + struct imx_mu_con_priv *cp = chan->con_priv;
>> + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
>
> Please do in reversed order from long to short
>
>> +
>> + u32 val, dat;
>> +
>> + val = imx_mu_read(priv, IMX_MU_xSR);
>> + val &= IMX_MU_xSR_TEn(cp->bidx) | IMX_MU_xSR_RFn(cp->bidx);
>> + if (!val)
>> + return IRQ_NONE;
>> +
>> + if (val & IMX_MU_xSR_TEn(cp->bidx)) {
>> + imx_mu_rmw(priv, IMX_MU_xCR, 0, IMX_MU_xCR_TIEn(cp->bidx));
>> + mbox_chan_txdone(chan, 0);
>> + }
>> +
>> + if (val & IMX_MU_xSR_RFn(cp->bidx)) {
>> + dat = imx_mu_read(priv, IMX_MU_xRRn(cp->idx));
>> + mbox_chan_received_data(chan, (void *)&dat);
>> + }
>> +
>> + return IRQ_HANDLED;
>> +}
>> +
>> +static bool imx_mu_last_tx_done(struct mbox_chan *chan)
>> +{
>> + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
>> + struct imx_mu_con_priv *cp = chan->con_priv;
>> + u32 val;
>> +
>> + val = imx_mu_read(priv, IMX_MU_xSR);
>> + /* test if transmit register is empty */
>> + return (!(val & IMX_MU_xSR_TEn(cp->bidx)));
>> +}
>> +
>> +static int imx_mu_send_data(struct mbox_chan *chan, void *data)
>> +{
>> + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
>> + struct imx_mu_con_priv *cp = chan->con_priv;
>> + u32 *arg = data;
>> +
>> + if (imx_mu_last_tx_done(chan))
>
> return true for tx_done?
> Or maybe better imx_mu_is_busy?
>
>> + return -EBUSY;
>> +
>> + imx_mu_write(priv, *arg, IMX_MU_xTRn(cp->idx));
>> + imx_mu_rmw(priv, IMX_MU_xCR, IMX_MU_xSR_TEn(cp->bidx), 0);
>> +
>> + return 0;
>> +}
>> +
>> +static int imx_mu_startup(struct mbox_chan *chan)
>> +{
>> + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
>> + struct imx_mu_con_priv *cp = chan->con_priv;
>> + int ret;
>> +
>> + ret = request_irq(cp->irq, imx_mu_isr,
>> + IRQF_SHARED, "imx_mu_chan", chan);
>
> This looks me to a bit strange as all virtual channels interrupts
> line actually are the same. And we request that same irq line
> repeatedly here with the same irq handler.
>
>> + if (ret) {
>> + dev_err(chan->mbox->dev,
>> + "Unable to acquire IRQ %d\n", cp->irq);
>> + return ret;
>> + }
>> +
>> + imx_mu_rmw(priv, IMX_MU_xCR, IMX_MU_xCR_RIEn(cp->bidx), 0);
>> +
>> + return 0;
>> +}
>> +
>> +static void imx_mu_shutdown(struct mbox_chan *chan)
>> +{
>> + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
>> + struct imx_mu_con_priv *cp = chan->con_priv;
>> +
>> + imx_mu_rmw(priv, IMX_MU_xCR, 0,
>> + IMX_MU_xCR_TIEn(cp->bidx) | IMX_MU_xCR_RIEn(cp->bidx));
>> +
>> + free_irq(cp->irq, chan);
>> +}
>> +
>> +static const struct mbox_chan_ops imx_mu_ops = {
>> + .send_data = imx_mu_send_data,
>> + .startup = imx_mu_startup,
>> + .shutdown = imx_mu_shutdown,
>> + .last_tx_done = imx_mu_last_tx_done,
>
> Do we really need this?
> Looking at the code, it seems .last_tx_done() is only called for polling mode.
> But what you set below is:
> priv->mbox.txdone_irq = true;
>
> Or am i missed something?
>
>> +};
>> +
>> +static int imx_mu_probe(struct platform_device *pdev)
>> +{
>> + struct device *dev = &pdev->dev;
>> + struct resource *iomem;
>> + struct imx_mu_priv *priv;
>> + const struct imx_mu_cfg *dcfg;
>> + unsigned int i, chans;
>> + int irq, ret;
>> +
>> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>> + if (!priv)
>> + return -ENOMEM;
>> +
>> + dcfg = of_device_get_match_data(dev);
>> + if (!dcfg)
>> + return -EINVAL;
>> +
>> + priv->dcfg = dcfg;
>> + priv->dev = dev;
>> +
>> + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> + priv->base = devm_ioremap_resource(&pdev->dev, iomem);
>> + if (IS_ERR(priv->base))
>> + return PTR_ERR(priv->base);
>> +
>> + irq = platform_get_irq(pdev, 0);
>> + if (irq <= 0)
>> + return irq < 0 ? irq : -EINVAL;
>
> Is it possible == 0?
>
>> +
>> + priv->clk = devm_clk_get(dev, NULL);
>> + if (IS_ERR(priv->clk)) {
>> + if (PTR_ERR(priv->clk) == -ENOENT) {
>> + priv->clk = NULL;
>> + } else {
>> + dev_err(dev, "Failed to get clock\n");
>
> The line looks not be quite meaningful as it may be defer probe.
>
>> + return PTR_ERR(priv->clk);
>> + }
>> + }
>> +
>> + ret = clk_prepare_enable(priv->clk);
>> + if (ret) {
>> + dev_err(dev, "Failed to enable clock\n");
>> + return ret;
>> + }
>> +
>> + chans = min(dcfg->chans, IMX_MU_MAX_CHANS);
>> + /* Initialize channel identifiers */
>> + for (i = 0; i < chans; i++) {
>> + struct imx_mu_con_priv *cp = &priv->con_priv[i];
>> +
>> + cp->bidx = 3 - i;
>> + cp->idx = i;
>> + cp->irq = irq;
>> + priv->mbox_chans[i].con_priv = cp;
>> + }
>> +
>> + priv->mbox.dev = dev;
>> + priv->mbox.ops = &imx_mu_ops;
>> + priv->mbox.chans = priv->mbox_chans;
>> + priv->mbox.num_chans = chans;
>> + priv->mbox.txdone_irq = true;
>> +
>> + platform_set_drvdata(pdev, priv);
>> +
>> + if (priv->dcfg->init_hw)
>> + priv->dcfg->init_hw(priv);
>> +
>> + return mbox_controller_register(&priv->mbox);
>> +}
>> +
>> +static int imx_mu_remove(struct platform_device *pdev)
>> +{
>> + struct imx_mu_priv *priv = platform_get_drvdata(pdev);
>> +
>> + mbox_controller_unregister(&priv->mbox);
>> + clk_disable_unprepare(priv->clk);
>> +
>> + return 0;
>> +}
>> +
>> +
>> +static void imx_mu_init_imx7d_a(struct imx_mu_priv *priv)
>> +{
>> + /* Set default config */
>> + imx_mu_write(priv, 0, IMX_MU_xCR);
>> +}
>> +
>> +static const struct imx_mu_cfg imx_mu_cfg_imx7d_a = {
>> + .chans = IMX_MU_MAX_CHANS,
>> + .init_hw = imx_mu_init_imx7d_a,
>> +};
>> +
>> +static const struct imx_mu_cfg imx_mu_cfg_imx7d_b = {
>> + .chans = IMX_MU_MAX_CHANS,
>> +};
>> +
>> +static const struct of_device_id imx_mu_dt_ids[] = {
>> + { .compatible = "fsl,imx7s-mu-a", .data = &imx_mu_cfg_imx7d_a },
>> + { .compatible = "fsl,imx7s-mu-b", .data = &imx_mu_cfg_imx7d_b },
>> + { },
>> +};
>> +MODULE_DEVICE_TABLE(of, imx_mu_dt_ids);
>> +
>> +static struct platform_driver imx_mu_driver = {
>> + .probe = imx_mu_probe,
>> + .remove = imx_mu_remove,
>> + .driver = {
>> + .name = "imx_mu",
>> + .of_match_table = imx_mu_dt_ids,
>> + },
>> +};
>> +module_platform_driver(imx_mu_driver);
>> +
>> +MODULE_AUTHOR("Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>");
>> +MODULE_DESCRIPTION("Message Unit driver for i.MX7");
>
> s/i.MX7/i.MX
>
> Regards
> Dong Aisheng
>
>> +MODULE_LICENSE("GPL v2");
>> --
>> 2.17.1
>>
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